Stuart Lancaster believes England will become serious contenders to win the 2015 World Cup if they can beat Wales today and win the Grand Slam.

The Millennium Stadium showdown will be a seismic title decider, with England chasing a first Six Nations clean sweep in a decade and Wales looking to retain their championship crown.

For England to triumph in those circumstances, just 14 months into their development as a team, would be a staggering achievement in its own right.

But Lancaster recognises it would also be a significant boost to England’s hopes of bringing the Webb Ellis Cup back to Twickenham in 2015.

“It would give you that inner confidence and belief that you can win in big games and finals,” Lancaster said.

“It’s a brilliant experience for the players and it will certainly help us with that long-term plan.

“The reality is that come 2015 we’re going to be playing Wales in a huge pool game. The more experience you can get of playing under the pressure of these type of games the better for the players.”

England have won 12 Slams but they have never sealed one in Cardiff and Lancaster feels there would be no better fixture in which to create a slice of history.

Lancaster said: “Both sides have got the chance to win the championship, so effectively it’s a shootout.”

England go into the match at full strength after Joe Launchbury (elbow) and Geoff Parling (shoulder) passed fitness tests to keep their places in the second row.

Lancaster has made four changes from the 18-11 win against Italy. Owen Farrell and Ben Youngs return in the half-backs, Tom Croft has replaced James Haskell at blindside flanker and Joe Marler got the nod ahead of Mako Vunipola.

Playing today: 15.30 Italy vs Ireland; 18.00 Wales vs England; 21.00 France vs Scotland.

Standings: England (4-0-0) 8; Wales (3-0-1) 6; Scotland (2-0-2) 4; Ireland (1-1-2) 3; Italy (1-0-3) 2; France (0-1-3) 1.